Black ink composition, ink set, recording method, recording matter and ink jet recording device

Abstract

Disclosed is a black ink composition containing a carbon black and a pigment represented by the following general formula (1):wherein p represents an integer of from 0 to 3. Also disclosed is an ink set containing at least one kind of such a black ink composition as at least one of a black ink composition and a light black ink composition.

What is claimed is:  
     
       1. A black ink composition comprising a carbon black and a pigment represented by the following general formula (1):                    
       wherein p represents an integer of from 0 to 3.  
     
     
       2. The black ink composition according to  claim 1  which is aqueous. 
     
     
       3. The black ink composition according to  claim 1 , further comprising at least one of an anionic surfactant, a nonionic surfactant and an amphoteric surfactant. 
     
     
       4. The black ink composition according to  claim 3 , wherein said nonionic surfactant is an acetylene glycol-based surfactant. 
     
     
       5. The black ink composition according to  claim 1 , further comprising a water-soluble organic solvent. 
     
     
       6. An ink set comprising, as a black ink composition or a light black ink composition, a black ink composition comprising a carbon black and a pigment represented by the following general formula (1):                    
       wherein p represents an integer of from 0 to 3.  
     
     
       7. An ink set comprising a plurality of black ink compositions comprising a carbon black and a pigment of formula (1):                    
       wherein the plurality of black ink compositions have different carbon black concentrations from one another, and  
       wherein any two of the plurality of black ink compositions satisfy the following relationship (2):  
       
         
             P 1 /K 1 >P 2 /K 2  (2)  
         
       
       wherein P1 and K1 represent the concentrations of the pigment of formula (1) and of the carbon black, respectively, in the black ink composition having a lower carbon black concentration between the two black ink compositions, and P2 and K2 represent the concentrations of the pigment of formula (1) and of the carbon black, respectively, in the black ink composition having a higher carbon black concentration between the two black ink compositions. 
     
     
       8. The ink set according to  claim 7 , wherein said black ink compositions comprising a carbon black and a pigment of formula (1) include a light black ink composition and a black ink composition. 
     
     
       9. The ink set according to  claim 6 , which is aqueous. 
     
     
       10. A recording method comprising: 
       ejecting a droplet of an ink composition so that said droplet is attached to a recording medium to effect printing,  
       wherein said ink composition is a black ink composition according to  claim 1 .  
     
     
       11. Recorded matter obtained by printing in accordance with a recording method according to  claim 10 . 
     
     
       12. An ink jet recording device comprising an electrostrictive element capable of oscillating according to electrical signal and being arranged such that the oscillation of said electrostrictive element causes ejection of a black ink composition, 
       wherein said ink composition is a black ink composition according to  claim 1 .  
     
     
       13. A recording method comprising: 
       ejecting a droplet of an ink composition so that said droplet is attached to a recording medium to effect printing,  
       wherein said ink composition is a constituent of an ink set according to  claim 6 .  
     
     
       14. An ink jet recording device comprising an electrostrictive element capable of oscillating according to electrical signal and being arranged such that the oscillation of said electrostrictive element causes ejection of a black ink composition, 
       wherein said ink composition is a constituent of an ink set according to  claim 6 .  
     
     
       15. The black ink composition according to  claim 1 , wherein the ink composition consists of a plurality of constituents providing the composition with a black color and a plurality of other constituents, said constituents providing the composition with the black color consisting essentially of the carbon black and the pigment represented by formula (1); said pigment represented by formula (1) being present in the ink composition in an amount effective to increase a resistance of the carbon black to yellowing when the black ink composition is exposed to ambient atmosphere as compared with a resistance of the carbon black to yellowing when the ink composition contains, in addition to the carbon black, another pigment instead of the pigment represented by formula (1). 
     
     
       16. The black ink composition according to  claim 15 , wherein the pigment represented by formula (1) is present in the ink composition in an amount of 0.05 to 1.5 parts by weight per 1 part by weight of the carbon black. 
     
     
       17. The black ink composition according to  claim 16 , wherein the other constituents comprise water, a surfactant and a water-soluble organic solvent. 
     
     
       18. The black ink composition according to  claim 17 , wherein p=0.